Biotech Values

[DewDiligence]

EXEL—It is important to note that the response rate in randomized discontinuation trials is typically lower than standard phase II studies since some patients with initial tumor shrinkage who do not qualify as responders switch to placebo at the time of randomization.

Corollary: The response rate to the novel agent in the randomized stage of a randomized-discontinuation trial is typically higher than the RR in the overall patient pool. This is because, at the time of randomization, more patients are typically pruned due to failure than are pruned due to an early response.

Development-stage biotech companies run randomized-discontinuation trials more often than Big Pharma does, and I think part of the impetus for these kinds of trials is to try to impress investors with the upwardly-biased stats from the randomized portion of the trial.